Chapter 19: How to Send a File

Sending large data files can be difficult.

Modern software systems have moved away from the concept of “files.” They don’t show you a folder full of image files; they show you a collection of photos. But files linger on, and will probably continue to do so for decades to come. And as long as we have files, we’ll need to send them to people.

The simplest, most obvious way to send a file is to pick up the device the file is stored on, walk over to the intended recipient, and hand it to them.

Carrying computers can be difficult — especially the earlier ones that were the size of a whole room — so rather than carry the whole computer, you can try detaching a piece of the computer containing the file. You can then bring this piece to the other person and let them transfer it to their own device. On a desktop-style computer, the files may be stored on a hard drive, which can often be removed without destroying the computer.

On some devices, though, file storage is permanently attached to the electronics, making removal more challenging.

A more convenient and less destructive solution is removable storage. You can make a copy of the file, put it on a device, then give the device to the person.

Carrying storage devices around is a surprisingly high-bandwidth way to transfer information. A suitcase full of MicroSD cards contains many petabytes of data; if you want to transfer very large amounts of data, mailing boxes of disk drives will almost always be faster than transferring them over the internet.

If you want to send data to a specific location that’s too far to walk, but not convenient to reach by mail — say, a nearby mountaintop — you could try using some kind of autonomous vehicle to carry it. A delivery drone, for example, could easily carry a small satchel of SD cards containing terabytes of data.

Quadcopter-style drones don’t work very well over long distances thanks to the limitations of batteries. If a drone has to carry its own battery, it can only hover for so long. If it wants to hover longer, it needs to carry a bigger battery, but that means more weight and faster power consumption. For the same reason that a house supported by jet engines [Note: For more on hovering houses, see Chapter 7: How to Move] can only hover for a few hours, small coaster-size drones typically have flight times measured in minutes, and the larger ones used for photography are usually limited to less than an hour in the air. Even if it flew very fast, a tiny drone carrying a MicroSD card could make it just a few miles before running out of steam.

You could increase your range by making the drone bigger, adding solar panels, flying higher, and going faster. Or you could turn to the real masters of efficient long-distance flight:

Butterflies.

Monarch butterflies travel thousands of miles during their migration across North America, with some traveling all the way from Canada to Mexico in a single season. If you look up during the spring or fall on the East Coast of the United States, you can sometimes spot them gliding by silently overhead, a few hundred feet above the ground. Their extreme range puts drones — and even many large aircraft — to shame.

You might think butterflies have an unfair advantage over battery-powered aerial vehicles, since they can stop to consume nectar and “recharge.” Butterflies will certainly refuel if they can, but they don’t necessarily need to. Another butterfly species, the painted lady (Vanessa cardui), is even more impressive: it flies from Europe to central Africa, a 4,000-kilometer flight that takes it over the Mediterranean Sea and the Sahara desert.

Butterflies make these journeys powered only by small reserves of stored lipids. They can fly so much more efficiently than drones in part by soaring — they seek out thermal columns and mountain waves, then hold their wings steady and ride the rising air upward like a vulture, hawk, or eagle.

If you want to send your file to someone who lives along the migration route, could you get a butterfly to carry it for you?

Butterflies can carry weights. Volunteers with groups like Monarch Watchtag tens of thousands to hundreds of thousands of monarch butterflies each year to track their migration and monitor their population (which has been in decline in recent decades). The smaller tags weigh about a milligram, but monarchs have completed their migration with larger tags that weigh 10 mg or more.

MicroSD cards weigh several hundred milligrams — comparable to the weight of a butterfly — so butterflies would have a hard time carrying them. But there’s no reason a storage device can’t be made smaller. MicroSD cards contain memory chips, and the storage density of these chips might be up to a gigabyte per square millimeter. Given those sizes, a butterfly could easily carry a tiny chip with a gigabyte of data. If your file is larger than that, you could break it up across multiple butterflies, and send multiple copies for redundancy.

When your data finally arrived at its destination, the recipient would have to check a lot of butterflies to assemble all the pieces of the file. You may need to develop some kind of touchless butterfly scanner that allows them to scan many butterflies at once.

You could avoid that problem — and increase your bandwidth dramatically — by using DNA-based storage. Researchers have stored data by encoding it into a DNA sample, then sequencing the DNA to recover it. Systems like this can achieve densities far beyond anything we do with chips — it’s possible to store and recover hundreds of petabytes of data using a single gram of DNA.

Each year, tens to hundreds of millions of monarch butterflies arrive in Mexico to spend the winter together in giant colonies in the mountains. If you tagged ten million of these butterflies with tiny pouches containing 5 mg of DNA storage each, the total capacity of the butterfly armada would be about 10 zettabytes — 10,000,000,000,000,000,000,000 bytes. That’s roughly the total amount of digital data in existence in the late 2010s.

If the Sun is warm, the winds are favorable, and it’s the right time of year, you could use butterflies to send someone the entire internet.

And Naitian Zhou of Ann Arbor, Michigan built an interactive tool that can generate arbitrary grammatical sentences using Python language tools and a database of book titles.

We’ll be reaching out to the runners-up to send them a signed book or a personalized drawing of their bookstore or library. Thank you so much to everyone who participated!

Tour updates

The How To book tour starts on September 3rd in Cambridge. I’ll be appearing in conversation with some very cool people, including researchers, journalists, and cartoonists. We’ll be discussing How To, science, comics, the destruction of the universe, and the ethics of hitting drones with tennis balls.

Some of the events are already sold out, so if you want to attend, you may want to get tickets now!

One of the most exciting things about writing How To was that, for a few chapters, I was able to reach out to some extremely cool people who were willing to apply their unique expertise to ridiculous tasks. Among those who generously agreed to help was Serena Williams.

Here’s a portion of the chapter “How to Catch a Drone”, in which Serena helped test whether tennis serves could be an effective countermeasure against flying robots … by taking a drone out onto a court and hitting tennis balls at it until it crashed.

How to Catch a Drone

A wedding-photography drone is buzzing around above you. You don’t know what it’s doing there and you want it to stop.

Let’s suppose you have a garage full of sports equipment— baseballs, tennis rackets, lawn darts, you name it. Which sport’s projectiles would work best for hitting a drone? And who would make the best anti-drone guard? A baseball pitcher? A basketball player? A tennis player? A golfer? Someone else?

There are a few factors to consider — accuracy, weight, range, and projectile size.

One sport I couldn’t find good data on was tennis. I found some studies of tennis pro accuracy, but they involved hitting targets marked on the court, rather than in the air.

So I reached out to Serena Williams.

To my pleasant surprise, she was happy to help out. Her husband, Alexis, offered a sacrificial drone, a DJI Mavic Pro 2 with a broken camera. They headed out to her practice court to see how effective the world’s best tennis player would be at fending off a robot invasion.

The few studies I could find suggested tennis players would score relatively low com- pared to athletes who threw projectiles— more like kickers than pitchers. My tentative guess was that a champion player would have an accuracy ratio around 50 when serving, and take 5–7 tries to hit a drone from 40 feet. (Would a tennis ball even knock down a drone? Maybe it would just ricochet off and cause the drone to wobble! I had so many questions.)

Alexis flew the drone over the net and hovered there, while Serena served from the baseline.

Her first serve went low. The second zipped past the drone to one side.

The third serve scored a direct hit on one of the propellers. The drone spun, momentarily seemed like it might stay in the air, then flipped over and smashed into the court. Serena started laughing as Alexis walked over to investigate the crash site, where the drone lay on the court near several propeller fragments.

I had expected a tennis pro would be able to hit the drone in five to seven tries; she got it in three.

For more on anti-drone strategies, sports projectile accuracy, a discussion with a robot ethicist about whether hitting a drone with a tennis ball is wrong, and many other topics, check out How To: Absurd Scientific Advice for Common Real-World Problems, available September 3rd (preorder: Amazon, Barnes & Noble, IndieBound, and Apple Books).

Want a personalized sketch of yourself as an xkcd-style stick figure? If so, you can preorder my new book How To and submit this form to enter a contest to win a personalized sketch of yourself!

Fifteen entrants will be randomly chosen to win a personalized stick figure portrait. I’ll draw a sketch of you and send it to you, so you can share it online, hang it on your wall, use it as your social media avatar, or whatever else you’d like.

There’s more information at the contest page here, and you can find out more about How To and read the introduction to the book here.

I’m really excited about it! Here’s the first preview of what’s inside:

Chapter list

How to Jump Really High

How to Throw a Pool Party

How to Dig a Hole

How to Play the Piano

How to Make an Emergency Landing

How to Cross a River

How to Move

How to Keep Your House from Moving

How to Build a Lava Moat

How to Throw Things

How to Play Football

How to Predict the Weather

How to Play Tag

How to Ski

How to Mail a Package

How to Power Your House (on Earth)

How to Power Your House (on Mars)

How to Make Friends

How to Send a File

How to Charge Your Phone

How to Take a Selfie

How to Catch a Drone

How to Tell If You’re a Nineties Kid

How to Win an Election

How to Decorate a Tree

How to Get Somewhere Fast

How to Be On Time

How to Dispose of This Book

In addition to the main chapters, the book also features short guides on topics including tornado chasing, dog walking, and highway engineering.

Introduction

This is a book of bad ideas.

At least, most of them are bad ideas. It’s possible some good ones slipped through the cracks. If so, I apologize.

Some ideas that sound ridiculous turn out to be revolutionary. Smearing mold on an infected cut sounds like a terrible idea, but the discovery of penicillin showed that it could be a miracle cure. On the other hand, the world is full of disgusting stuff that you could smear on a wound, and most of them won’t make it better. Not all ridiculous ideas are good. So how do we tell the good ideas from the bad? We can try them and see what happens. But sometimes, we can use math, research, and things we already know to work out what will happen if we do.

When NASA was planning to send its car-size Curiosity rover to Mars, they had to figure out how to land it gently on the surface. Previous rovers had landed using parachutes and air bags, so NASA engineers considered this approach with Curiosity, but the rover was too large and heavy for parachutes to slow it down enough in Mars’s thin atmosphere. They also thought about mounting rockets on the rover to let it hover and touch down gently, but the exhaust would create dust clouds that would obscure the surface and make it hard to land safely.

Eventually, they came up with the idea of a “sky crane” —a vehicle that would hover high above the surface using rockets while lowering Curiosity to the ground on a long tether. This sounded like a ridiculous idea, but every other idea they could come up with was worse. The more they looked at the sky crane idea, the more plausible it seemed. So they tried it, and it worked.

We all start out life not knowing how to do things. If we’re lucky, when we need to do something, we can find someone to show us how. But sometimes, we have to come up with a way to do it ourselves. This means thinking of ideas and then trying to decide whether they’re good or not.

This book explores unusual approaches to common tasks, and looks at what would happen to you if you tried them. Figuring out why they would or wouldn’t work can be fun and informative and sometimes lead you to surprising places. Maybe an idea is bad, but figuring out exactly why it’s a bad idea can teach you a lot—and might help you think of a better approach.

And even if you already know the right way to do all these things, it can be helpful to try to look at the world through the eyes of someone who doesn’t. After all, for anything that “everyone knows” by the time they reach adulthood, every day over 10,000 people in the United States alone are learning it for the first time.

That’s why I don’t like making fun of people for admitting they don’t know something or never learned how to do something. Because if you do that, all it does is teach them not to tell you when they’re learning something . . . and you miss out on the fun.

This book may not teach you how to throw a ball, how to ski, or how to move. But I hope you learn something from it. If you do, you’re one of today’s lucky 10,000.

6:30 – 7:30 PMCONDENSING AN IDEA: MAKING THE DIFFICULT PALATABLELocation: Room 26ABHow do you distill a story down to its main components? Comics often call for brevity, but how does that work with a complex story or idea? Comic-Con special guests discuss how they delve into their complex worlds of comics and come out the other side with stories we readily consume. Panelists include Kurt Busiek (Avengers), Jon B. Cooke (Comic Book Artist), and Randall Munroe (xkcd), along with Dani Colman, Tea Fougner (editorial director for comics, King Features Syndicate), and moderator Barbara Dillon.More info:https://sched.co/Rlvs

10:00 – 11:00 AMSPOTLIGHT ON RANDALL MUNROE- How To: Absurd Scientific Advice for Common, Real-World ProblemsLocation: Room 4Randall Munroe, creator of xkcd, discusses his new book How To, a guide to using science to turn everyday problems into much bigger, more exciting problems. Learn how to cross a river by boiling it, get tips on how to make skiing much more dangerous using liquid oxygen, and hear about his experience asking famous experts the most ridiculous questions he could think of.More info: https://sched.co/Rra2

3:00PMADVANCED GALLEY SIGNINGLocation: Random House Booth #1515Come by the Penguin Random House booth to get a signed advanced copy of Randall Munroe’s forthcoming book “HOW TO: Absurd Scientific Advice for Common Real-World Problems.” Tickets are required for all signings at the Penguin Random House book and are available first come, first serve and while supplies last. Tickets will be distributed approximately 10 minutes before the start time.

SUNDAY JULY 21, 2019

1:00 – 2:00 PMSHORT FORM COMICS FOR EVERY READERLocation: Room # 28DEAminder Dhaliwal (Woman World), Ebony Flowers (Hot Comb), Kevin Huizenga (The River at Night), Randall Munroe (What If), and Sophie Yanow (The Contradictions) are masters of the short form comic, whether serialized online, in pamphlets, or collected in graphic novel form. Sarah Mirk, senior editor at The Nib, leads a conversation on pacing, flow from story to story (or strip to strip), and much more.More info: https://sched.co/Rsrz

How to invite me to your town

Don’t see your city on the list? You can invite me! I’ll be adding one more US stop to my tour based on the results of a challenge.

The challenge: Write the best story using nothing but book covers.

Arrange the titles of your favorite books into sentences that tell a story, assemble a single continuous line of people holding up the covers, and take a photo or video documenting your feat. You can make the story as long as you want, but each book needs to be held by a different human.

Creative grammar is fine, and you’ll get extra credit for including as many books and people as possible.

I’m excited to announce that I have a new book coming out! It’s titled How To: Absurd Scientific Advice for Common Real-World Problems, and it’s an extremely unhelpful guide to solving everyday problems.

How To is an instruction manual for taking everyday problems and using science and creative thinking to turn them into much bigger and more exciting problems. It teaches you how to cross a river by boiling it, outlines some of the many uses for lava around the home, and walks you through how to use experimental military research to ensure that your friends will never again ask you to help them move.

From changing a lightbulb to throwing a pool party, it describes unusual ways to accomplish common tasks, and analyzes what would happen to you if you tried them. In addition to being a profoundly unhelpful self-help book, it’s an exercise in applying math, science, and research to ordinary problems, and a tour through some of the strange and fun science underlying the world around us.

Sadly, my current Thing Explainer book tour doesn’t stop in the UK (although you can come see me at London’s Royal Institution via live videolink on December 7th—tickets here).

However, in lieu of an in-person visit, my publisher and I have put together a special puzzle for UK readers to solve.

The puzzle has two steps. Step one is to find out where step two is.

For step one, you can pick any one of five cities. Here’s a helpful map, followed by some interesting facts about each city.

Bristol: 2.72km
A major port, built on seven very steep hills, Bristol has long been home to explorers and inventors – and the UK’s oldest dinosaur. In 1497 John Cabot sailed out of Bristol to try to find a better route to Asia and discovered Newfoundland instead. Isambard Kingdom Brunel designed this tall road in 1830. It took another 34 years to finish, and he lived only to see the towers built (one in the suburb the road is named after).

London: 0.44km
A city famous (in song) for its bridges falling down and (in stories) for its streets not being paved with gold. A fifth of all the pieces everything is made of were discovered in London, including hydrogen (originally called ‘inflammable air’) in Clapham, and ten by Humphrey Davy here. There’s even a red world space car in the Science Museum.

Oxford: 0.51km
Inaccurately described by writers as ‘a city of dreaming spires’, Oxford is obsessed with thing explaining. Oxford professors CS Lewis, Tolkien and Lewis Carroll turned Christianity, Anglo Saxon and mathematics into successful works of fiction. This college lays claim to William of Ockham who came up with the principle of Ockham’s razor, that the most straightforward answer is usually the right one. They would all agree that the writing stick is mightier than the sword.

Edinburgh: 1.85km
Built on an extinct volcano, this city is famous for its body snatchers, for Peter Higgs (big tiny thing hitter) and for Dolly the sheep. Alexander Graham Bell was educated here, and missed it so much when he moved across the Atlantic that he invented the telephone, precursor to the hand computer.

Cambridge: 0.05km
The university was founded in 1209 by students on the run from the Oxford police. Home to Isaac Newton, famous for working out colours of light and for understanding how dangerous sitting under an apple tree could be; a descendant of that tree remains near his room. Also home to Stephen Hawking and 89 Nobel prizewinners (31 more than Oxford), and the Mathematical bridge.

Good luck!

Prizes will include signed copies of Thing Explainer and limited-edition posters and mobiles. There will also be one very special first prize.

Want to try writing using only simple words? Here’s a writing checker you can use: xkcd.com/simplewriter.

To help me write the words in my Up Goer Five picture, I taught my computer to watch my writing and tell me when one of the words I used wasn’t in the top ten hundred. After I put up my Up Goer picture, other people made things to check writing, too (like this one).

When I decided to write Thing Explainer, I went back to the writing checker I had used and made it better. Now, I’m happy to be able to share it with everyone!

To use it, just touch here and start writing. If you use a word that’s not in Thing Explainer’s set of the ten hundred, the word will turn red. (I usually count all forms of a word, like “kick” and “kicked,” together as one word, although there are a few special cases where I don’t.)

Have fun explaining things!

A note on the words: Some words are used more often in certain kinds of writing and talking than in others, which means different ways of counting words will give different answers for which ones we use the most. The set of ten hundred words in Thing Explainer comes from putting together many ways of counting how much people use a word to come up with a single set of ten hundred words that should sound familiar and simple to lots of people.

Thank you to James Zetlen, who helped make the word checker work on other people’s computers and not just mine.